Wire connection



March 14, 1939. R 2,150,404

WIRE CONNECTION Filed Jan. 2'7, 1937 INVENTOR AHSCHAFER A 7' TORNE V Patented Mar. 14, 1939 UNITED. STATES 1 PATENT OFFICE, f

WIRE CONNECTION Arthur H. Schafer, Flushing, N. Y., assignor to .Bell Telephone Laboratories, Incorporated, New

York, N. Y., a corporation of New York Application January 27, 1937, Serial No. 122,527 1 Claim. (Cl. 174-87) This invention relates to wire connections and more particularly to a wire connection in which a wire of comparatively small gauge is attached to a conductor wire of comparatively large gauge.

The object of the invention is to provide a strong and durable connection between the wires above mentioned.

A feature of the invention resides in a splice by means of which the wires are connected.

Another feature resides in protective means applied to the spile to protect 'the wires at the point 01' splice from strain.

In the drawing:

Fig. 1 is a side view partly in section of a conductor wire together .with supporting means and protective coverings for the wire;

Fig. 2 is a side view of the conductor wire oi Fig. 1' and a lead wire and illustrates one step in the manner in which the two members are attached;

Fig. 3 is a side view oi. the conductor and lead wires shown in Fig. 2 and shows a further development;

Fig. 4 is a side view, partly insection, of a completed connection between the two wires;

Fig. 5 is a. view in perspective and partly in section 01' an electrical device in which the invention is used; and,

Fig. 6 is a sidewview, partly in section, of a portion of the device shown in Fig. 5.

Figs. 1, 2, 3 and 4 are drawn on enlarged scales relative to Figs. 5 and 6.

In electrical devices of the wire wound type, the resistance wire forming the resistance element is sometimes of comparatively small gauge andis helically wound on a cord of insulating material. In some cases a covering of insulating material is provided over the wire wound on the cord. The resistance element comprising the wirewound cord and insulating covering is wound on a spool of insulating material and electrical con-- nections are made between the resistance wire and terminals supported on the spool. The resistance wire in some cases is of such small gauge that it is found desirable to provide a wire stronger and of larger gauge than the resistance wire, as a lead wire between an end of the resistance wire and the terminal to prevent accidental disconnection of the parts. The present invention provides a strong and durable connection between an end of the comparatively small gauge resistance wire and the wire of larger gauge.

In Fig. 1 a resistance wire I of. comparatively small gauge is helically wound on a cord 2 of insulating material, the cord 2 thus serving as a support for the resistance wire I. A covering 3 of insulating material is applied over the winding of resistance wire, the covering 3 being in the form of a sleeve. The covering 3 may be made of 5 any suitable insulating material. An outer covering 4 of insulating material is applied over the covering 8.

The resistance wire I supported on the cord 2 of insulating material and enclosed in the 'pro- 10 tective coverings 3 and 4 shown in Fig. 1 may be wound on a spool 5 of insulating material as shown in Fig. 5. The spool 5 may have end flanges 8 in which terminals 1 are suitably supported.

To electrically connect the resistance wire I to the terminals 1 lead wires 8 of larger gauge than the resistance wire I are provided. One endor the lead wire 8 is attached to a terminal I in any suitable manner, for instance by windgo ing a portion of the lead wire 8 around the terminal and by soldering the parts togethter. The other end of the lead wire 8 is attached to the resistance wire I.

The lead wire 8 comprises a suitable length of 25 conductor wire 9 having a covering III of insulating material. As shown in Fig. 2, a portion of the insulating covering III is removed from the conductor wire 9 to provide an uncovered portion suitable for making electrical connection be- 30 tween the resistance wire I and the conductor wire 9. A portion of each insulating covering 3 and 4 enclosing the resistance wire I is also removed leaving the exposed portions of the resistance wire I and the cord 2 of insulating ma- 35 terial. The'lead wire 8 is placed parallel to the wire-wound cord 2 and an end of the resistance wire I is helically wound on the bared end of the conductor wire 9, and may be further secured thereto by soldering the parts together as shown 40 at II. The point of winding of the resistance wire I on the conductor wire 9 advanced beyond the exposed end of the cord 2 to bring a portion of the covering III of insulating material of the lead wire 8 parallel to and adjacent the 45 exposed portion of the cord 2. The bared end of the cord 2 with several turns'of the resistance wire I thereon is then lashed to the lead wire 8 as shown in Fig. 3, the parts being bound together by means of thread I2, the thread I2 50 being wrapped around the cord 2 and the insulating covering III of the lead wire 8 adjacent the bared end and lashing the parts together. I have found that silk floss serves well as a material to lash the parts together.

Whentheleadwirelislashedtothebared endoi' oordlasshowninl'ig.3,thelead wirelisthenbentbackalongitseitasshownin Fllztb extendparalleltothebaredendot thecordl andthe pointatwhich thepartsare bound together. A sleeve "of insulating material is then awlied over an end or the insulating covering 4 of the resistance element and over the bent back portion of the lead wire I. The sleeve II closely embraces the end portion of the insulating covering 4 or the resistance element adjacent the bored end or the cord 2 and embraces the bent back portion 01' the lead wire I to hold the bent back portion of the lead wire I against the lashing II. The free end portion of the lead wire I may be connected to a termiml 1 in any convenient manner such for instance as by removing a portion of the insulating covering II from the conductor wire I and by soldering an end of the wire 9 to the terminal I. V

In Figs. 5 and 6 a covering II 01! insulating material is applied over the windings o! the re sistance element on the spool I. The lead wire I is shown in Fig. 6 as extending over an annular shoulder II on the inner face of the spoolhead I, and througha slot II in the outer iace oi the spoolhead to a terminal i. The bared end I! oi. the lead wire I is wound around the terminal I and is soldered thereto. The lead wire 8 is lashed against the shoulder I! by means of a cord II, the cord II being wound around the shoulder il over the lead wire I and ends 01 the cord being tied together as shown at IS. The covering It extends over the lead wire I and over the turns 01' the resistance wire element on the spool. The covering it may be made oi any suitable insulating material but for the purpose oi illustration is shown in the drawing as being a serving of thread. To further protect the resistance winding against the entrance of moisture a coating 20 oi insulating material is applied over the covering It. The slot II in the spoolhead I is filled with an insulating cement material after the lead wire I has been placed therein. An apertured disc ii of insulating material is secured by means of insulating cement to the outer race or the spoolhead i.

What is claimed is:

In a wire connection, a flexible cord of insulating material, a wire helicaliy wound on said cord, an insulating covering surrounding said cord and said wire, a lead wire. a covering 0! insulating material thereon, a bored end portion 01' said cord with the helicaliy wound wire thereon placed adjacent and parallel to a covered portion of said lead wire, a lashing oi thread binding the covered portion of said lead wire to said bared end portion or said cord. a bated portion or said lead wire extended beyond the point oi lashing, a portion of said first-mentioned wire helically wrapped into connection with said bared portion of said lead wire, an insulated portion of said lead wire bent back on itself and against said lashing, and a sleeve of insulating material surrounding the connected portions or said wires.

the lashed portions oi! said wires and bearing against the insulating coverings of said wires.

ARTHUR H, SCHAFER. a 

